Really sorry but I just realised the forum was getting hit with some serious spam.

In total I have had to delete over 70,000 topics mainly about essay writing.

I have also enabled further validation checks on new user registrations and restrictions on how many posts a new user can make.

Due to the volume of posts I was unable to use the admin panel as it kept timing out so I resorted to writing some SQL queries and running them over SSH (even PHPMyAdmin was timing out).

In case it is of interest, I had to first kill SQL queries that were running from my attempts to sort this out from the admin panel as these were placing locks on the tables which resulted in this error every time I tried to run a delete query on the data: